JPS601373B2 - Method for producing amorphous alloy with excellent strength and corrosion resistance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an amorphous alloy with excellent strength and corrosion resistance.

Recently, there have been advances in fiber-reinforced or laminated composite materials.
There is a strong demand for high quality and low cost metal fibers and foils as the materials.

Metals are generally excellent materials in terms of strength, etc., but making them into fibers or foils requires many steps.
As a result, a large amount of manufacturing cost is inevitably required.

For example, metal whisker crystals are an ideal fiber material with high strength, but they are not only expensive but also difficult to mass produce because they are produced through chemical reactions and phase changes such as precipitation from solutions, reduction, and vapor condensation. be. Furthermore, thin metal wires, such as piano wires, are extremely expensive because they require repeated cold drawing and intermediate drawing processes. The same applies to metal foil. Therefore, methods of directly producing metal fibers and metal foils from molten metal have been studied as an inexpensive means of producing these materials. However, metal fibers and foils produced by conventional methods have been extremely inadequate in terms of strength and rutting properties. However, recently,
An alloy of iron or nickel containing more than 10% of phosphorus and several percent of carbon or even a few percent of chromium is sprayed from a molten state onto a metal conductor with good thermal conductivity to rapidly solidify it and make it amorphous. It has been found that a material with excellent strength and rut spreadability can be obtained by using this method. However, obtaining such an amorphous state depends to a large extent on the component system and cooling conditions, and the component systems that have been published have been empirically limited to the above range. Therefore, the present inventors conducted extensive research on the component system and manufacturing conditions to obtain an amorphous state, and first determined that iron, cobalt, and nickel, which are transition elements in Group 8 of the Periodic Table, or any of these as the basic component. It has been found that it is sufficient to add one or more types of nitrogen, aluminum, and tin adjacent to the metalloid element, and further two types of the metalloid element, based on the mixed components of the metalloid element.

The amorphous metal obtained in this way has significantly superior strength and elongation when compared to conventional crystalline rapidly solidified metals.
It has sex. However, if corrosion resistance could be further improved, it would be extremely effective in expanding the range of uses. Therefore, the present inventors investigated the effects of various alloy additions based on the above-mentioned basic ingredients and found that ``titanium, zirconium, and hafnium, elements of the weekly table umbrella group, are effective for this purpose.''Furthermore, It is expected that the hydrogen storage capacity will increase when iron and titanium are combined. This property will become an important technology for the use of hydrogen, which has recently attracted attention as a non-polluting energy source. According to the knowledge of Among the eutectic temperatures of the binary alloy of the added metalloid element and either the adjacent element or the metalloid element, it is effective to keep the temperature within +15,000 from the highest temperature.

Furthermore, regarding cooling conditions, it is necessary to rapidly cool the alloy from a molten state at a rate of 1 degree Celsius or more per second. In this case, an amorphous structure refers to a state in which diffraction lines characteristic of metal crystals are not observed in ordinary X-ray diffraction.

In addition, metalloid elements refer to boron, carbon, poppy, element, and phosphorus. In the present invention, the three elements iron, cobalt, and nickel were targeted as the Group 8 transition elements that form the matrix of the alloy, but it is easy to see that other Group 8 elements may have similar effects. Conceivable. It goes without saying that there is no problem even if unavoidable impurities are included as ingredients.
The theoretical basis on which the combination of the above components makes it easy to create an amorphous metal alloy and has excellent corrosion resistance is currently unclear.

The present invention was obtained as a result of systematic experiments on the relationship between the tendency to form an amorphous structure, the type of added element, and the cooling rate. The research conducted by the present inventors has revealed the regularity of the types of added elements on the weekly table. One of the key points of the present invention is to ensure an amorphous state by combining a group 8 transition element, an element adjacent to a metalloid element, and a metalloid element, and to improve the properties of the metalloid element, an umbrella group element is added. It consists in adding. Conventionally, amorphous metals based on iron, nickel, or palladium have been announced, but as a result of a series of studies in which the iron base was replaced with a metal element, the present inventor found that not only nickel but also cobalt can be used to replace the base iron. Although amorphous metals can be obtained, we have found that substitution with manganese and copper, which are out of Group 8, is difficult to make amorphous metals.On the other hand, as elements combined with these base components, conventional %, and simultaneous addition of carbon number % was known.

However, the present inventors conducted extensive research on these elements, and found that addition of nitrogen, sulfur, and aluminum, which are adjacent to metalloid elements on the weekly table, was also effective over a wide range. It was discovered that amorphous state can be maintained even if the addition of the elements of the Chrysanthemum group up to a certain limit is achieved.Furthermore, regarding the amounts of these additions, previous research has shown that no additive elements other than iron or nickel are added. Their total amount is limited to about 20 atomic %, and no regular guidelines for component design have been obtained.

As a result of extensive experiments, the inventors of the present invention determined that the melting point of the alloy was one of the criteria. This is determined by the relationship with the eutectic temperature of the binary alloy.In other words, as mentioned earlier, it is necessary to lower the melting point of the alloy to a certain level, and this is due to the fact that the melting point of the alloy , nickel and any one of added nitrogen, sulfur, aluminum, or metalloid element, plus one point higher than the highest eutectic temperature of the binary alloy.
It has been found that it is effective to adjust the composition by including the umbrella group elements so that it is 5,000 or less, preferably 10,000 or less. Of course, even if the alloy components are adjusted in this way, it is impossible to obtain an amorphous metal depending on the cooling rate, and it is necessary to solidify and cool the metal from a molten state sufficiently quickly.

The first area that requires fastening is during solidification, but after solidification,
When kept at a high temperature for a long time, crystallization occurs due to atomic diffusion, so it is necessary to maintain a sufficient cooling rate even after solidification. Strictly speaking, it is conceivable that the required cooling rates are different during solidification and after solidification, but it is difficult to actually control them separately. The present inventors have found from experiments using various cooling rates and theoretical predictions that it is necessary to cool the material at a rate of 1° C./second or more until crystallization stops at about 300° C. The amorphous alloy thus obtained has superior strength, ductility and corrosion resistance compared to ordinary crystalline rapidly solidified alloys.

Therefore, applications include wire ropes, steel cords, filters, fiber-reinforced composite materials, concrete reinforcement materials, meshes, soundproofing and earthquake-proofing materials, as well as hydrogen storage materials. The present invention is extremely significant in that it has discovered a law that goes beyond the conventional limited experience when designing an amorphous alloy, and has obtained excellent properties. Example 1 The melting point of the 65 atomic % Fe-10 atomic % P-10 atomic % C-5 atomic % AI-10 atomic % Ti alloy is 1120°, which is the melting point of iron, nitrogen, aluminum, and metalloid elements. It is lower than the higher eutectic temperature of the two elements, which is 1165°C, which is the eutectic temperature of the Fe-AI system (see Figure 2).

The metal fiber, which was rapidly solidified from the molten state by cooling at 1° C./second, showed an amorphous state. Its characteristics are shown in the table below. Example 2 Further, an alloy having the composition below was rapidly solidified from a molten state at a cooling rate of 1°C/sec, and exhibited an amorphous state, and its properties were as follows.

Moreover, the corrosion resistance was also good. Brief Description of the Drawings Figure 1 is an X-ray diffraction photograph of an iron-10 atom% P-10 atom% C-5 atom% M-10 atom% T8E crystalline alloy produced by the method of the present invention, showing an amorphous state. This is a photo shown.

FIG. 2 is a phase diagram of a binary iron-aluminum alloy. The melting point of the iron-10 atom% phosphorus-10 atom% carbon-5 atom% aluminum-10 atom% titanium alloy is 112,000 from the eutectic temperature of the binary system of iron and aluminum, 1165oo.
5000 higher and within 1315oo (hatched area). Ta1 Futa Z diagram

Claims (1)

[Claims] 1 One or more of iron, cobalt, and nickel as basic components, one or two or more of nitrogen and aluminum, and two or more of boron, carbon, phosphorus, and silicon as metalloid elements. , one or two of titanium and zirconium, whose melting point is the highest of the eutectic temperatures of the binary system of the basic components constituting the alloy, added nitrogen, aluminum, and any of the metalloid elements mentioned above. The alloy is contained so that the temperature is within +150°C from the high temperature, and the alloy is heated to 300°C from the molten state.
A method for producing an amorphous alloy with excellent strength and corrosion resistance, which comprises rapidly solidifying an amorphous alloy at a cooling rate of 10^5°C/sec or more over a temperature range of